A laparoscope is described and, more particularly, a laparoscope which is self-cleaning for maintaining a viewing field during use.
Laparoscopic surgery is a minimally invasive surgical technique performed in the abdomen through multiple small incisions. One of the surgical tools used is a laparoscope. The laparoscope is an imaging device comprising a lens tube which acquires an image of a target area in an objective lens at its distal end and a relay lens system within the lens tube. The laparoscope conventionally includes a camera which produces a video image of the target area, such as tissue within the body cavity of a patient, for display on a video monitor. In one application, a laparoscope is inserted through a transcutaneous trocar in a small incision and provides visualization while performing surgery in the abdominal cavity (FIG. 11).
One of the main problems with laparoscopic surgery is the issue of visibility of the surgical area through the lens. Visibility is reduced due to fogging, abdominal bleeding, and tissue smearing. Fogging of the laparoscope occurs because there is a difference in room temperature and abdominal temperature, causing condensation on the distal lens. Abdominal bleeding can occur as a result of the surgical procedure and can obscure vision when blood covers the lens. Finally, tissue inside of the trocar can smear the lens upon insertion of the laparoscope.
The physician typically removes the laparoscope from the patient for cleaning the lens and reinsertion into the abdomen. However, removal and reinsertion interrupts the flow of surgery and is time consuming, which can increase patient complications and medical expenses and lead to bacterial issues. Further, the path from the trocar entry to the site of surgery is cluttered and can leave debris on the lens.
Internal cleaning devices are available, but can readily become misplaced inside the patient if broken and some have only a limited number of uses before requiring replacement.
A mechanical solution utilizes carbon dioxide to create an air curtain near the tip of the lens, which prevents any debris from entering. Debris that passes through the air curtain can be cleaned either manually or through a built-in saline wash. However, this solution increases the bulk of the instrument and requires the use of larger unconventional incisions.
For the foregoing reasons, there is a need for keeping the view of the laparoscope uninhibited during surgery. Ideally, the laparoscope is fog-resistant, shielded from splashes, and otherwise remains clean in the body throughout surgery.